// GenericsNote: Converted.
/*
 *  Copyright 2001-2004 The Apache Software Foundation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
package org.apache.commons.collections15;

import java.io.Serializable;

/**
 * Transformer implementation that calls a Factory and returns the result.
 *
 * @author Matt Hall, John Watkinson, Stephen Colebourne
 * @version $Revision: 1.1 $ $Date: 2005/10/11 17:05:24 $
 * @since Commons Collections 3.0
 */
public class FactoryTransformer<I, T>
		implements Transformer<I, T>, Serializable {

	/**
	 * Serial version UID
	 */
	static final long serialVersionUID = -6817674502475353160L;

	/**
	 * The factory to wrap
	 */
	private final Factory<T> iFactory;

	/**
	 * Factory method that performs validation.
	 *
	 * @param factory
	 *            the factory to call, not null
	 * @return the <code>factory</code> transformer
	 * @throws IllegalArgumentException
	 *             if the factory is null
	 */
	public static <K, T> Transformer<K, T> getInstance(Factory<T> factory) {
		if (factory == null) {
			throw new IllegalArgumentException("Factory must not be null");
		}
		return new FactoryTransformer<K, T>(factory);
	}

	/**
	 * Constructor that performs no validation. Use <code>getInstance</code> if
	 * you want that.
	 *
	 * @param factory
	 *            the factory to call, not null
	 */
	public FactoryTransformer(Factory<T> factory) {
		super();
		iFactory = factory;
	}

	/**
	 * Gets the factory.
	 *
	 * @return the factory
	 * @since Commons Collections 3.1
	 */
	public Factory<T> getFactory() {
		return iFactory;
	}

	/**
	 * Transforms the input by ignoring the input and returning the result of
	 * calling the decorated factory.
	 *
	 * @param input
	 *            the input object to transform
	 * @return the transformed result
	 */
	@Override
	public T transform(I input) {
		return iFactory.create();
	}

}
